Field of the Invention
The invention relates in general to welding and is a method for manufacturing thin-walled hollow bodies of concentric, largely non-corrosive, high-temperature stable, and non-scaling metal layers and to a device for carrying out the method.
Thin-walled hollow bodies, for example, pipes and pipe bends of concentric metal layers can in the chemical industry, especially in high-temperature installations, in which temperatures of up to 1200.degree. occur, be required to have simultaneously several properties like corrosion resistance, high-temperature stability, and resistance of scaling.
For the specific thin-walled structural components of the previously mentioned installations non-coated pure materials are used. Due to the method of manufacture, structural parts of these materials have disadvantages, because the individual materials of which they are made, can simultaneously possess only to a limited extent several material characteristics, like corrosion resistance, high-temperature stability and resistance of scaling.
For these reasons, an aim is to find manufacturing methods, which permit constructing, for example pipes and pipe bends of different kinds of working materials structured in layers, of which each kind of working materials is intended to have primarily only one of the mentioned working material characteristic.